Double-tube core-barrel.



M. AHEARN. I

DOUBLE TUBE COBB BARREL.

APPLICATION mum mm. a, 1010.

982,456. Patnted Jan. 24, 1911.

a jfl [Q J Ji Q I fii i 19 g a g2 g I J 2/ f 23 Zj :1 T Z2 2 L I J2 Y J1 l Witnesf v W -W by '7 16 2; 1 I Attorneys ing its stationary positionby the column or 'volume of water under pressure as will be of Fig. 1.

disposed wall 6 and a wall 7 which is lo- MICHAEL AHEARN, 01? DENVER,COIiORADO.

DOUBLE-TUBE CORE-BARREL.

Specification of Letters Patent.

Application filed September 3, 1910. Serial N02 580,353.

To all whom it may concern.-

Be it known that I, MICHAEL AHEARN, a l citizen of the United States,residing at Denver, in the county of Denver and State of Colorado, haveinvented a newand useful Double-Tube Core-Barrel, of which thefollowing; is a specification.

This invention has relation to double tube core barrels and consists inthe novel construction and arrangement of its parts as hereinafter shownand described.

The object of the invention is to provide a core barrel in which twotubes are employed, means being employed for rotating the outer tube,while the inner tube is held stationary. Antifriction devices areinterposed between the adjoining members of the two tubes and theadjoining members of the tubes are so fitted together thatnotwithstanding the fact thatwater may be forced under pressure betweenthe tubes it can have no ingress to the chamber in which the anti-'friction devices are located, thus the said anti-friction devices areprotected against the entrance of grit or other foreign substancesxvliicli have a tendency to wear the same.

A further object of the invention is to so assemble and shape thepartsthat the inner tube is materially assisted in retainexplainedhereinafter.

In the accompanying drawing :--Figure 1 is a vertical longn'tudinalsectional view of the core barrel. Fig. 2 is a transverse sectional Viewof the same cut on the line 2-2 The outer tube 1 is provided at itslower end with a drill bit 2 of usual pattern. The bit 2 is rovided atits upper portion with an annu ar beveled surface as is usual in suchparts and a split ring 4 is adapted to rest against the said annularbeveled surface 3. The ring 4 tapers from its upper edge to its loweredge and is provided upon its periphery with a number of grooves 5 eachof which is provided with a radially cated at a tangent to a circlestruck from the center or axis of the tube 1.- The said grooves extendfrom one end of the ring 4 to the other and serve as unobstructed waterafter. A coupling plug 8 is inserted in the upper end of the tube 1 andis providedwlth a threaded bore 9 which may receive the end of a drillred. A hood 10 depends from the plug 8 and is slightly less in diameterthan the diameter-at the inner peri ihery of the tube 1. The plug .8 isprovit ed with an annular roove 11 which is located at the upper enc ofthe reduced hood 10 and passages 12 extend from the bore 9 to the saidannular groove 11. The reduced hood 10 is provided with a centrallypositioned bore 13 in which is journalcd a stem 14. Ball retaining rings15 and 15 are located in the hood 10 and are fixed with relation to thesame. The stem 14 hcreinbefore mentioned is journaled in the said rings15 and 15. Rings 16 and 16 are loosely mounted in the hood l0 andloosely receive the stem 14. A collar 17 is fixed to the stem 14 at apoint bet-ween the rings 16 and 1(5' and hold the said rings at a properdistance apart. Bearing balls 18 are interposed between the rings 15 and16 and the rings 15' and 16' and are also located within the hood 10. Aplug 19 is screw-threaded in the lower end of the hood 10 and fitssnugly against the end of the same. The stein 14 is journaled in thesaid plug 19. The plug 19 is provided with a smooth or machined lowerface 20 and a plug 21 is attached to the lower end of the stem 14 andits upper face fits snugly against the smooth surface 20 of the plug 19.

An inner tube 22 is located in the tube 1 and is attached at its upperend to the plug 21, the outer periphery of the inner tube 22 is spacedfrom the inner periphery of the outer tube 1. The plug 21 is providedwith a by-path 23, one end of which communicates with the space betweenthe periphery of the said plug, and the inner periphery of the tube 1and the other end thereof communicates with the interior of the tube 22.

During the drilling operation, the plug 8 is rotated and at the sametime water is forced through the drill run, (not shown) into the bore 9of the said plu 8. From the bore 9 the water passes t rough the passages12 into the annular recess rovided at the upper end ofthe hood 10. T ewater passes down through the space between the Patented Jan. 24, 1911.

outer periphery of the hood and the inner split. ring 4 to the pointwhere the bit 2 is operat in upon the rock. By reason of the fact thathe upper face of the plug 21 fits snugly against the lowermost face 20of the plug 19 it is impossible for the water or grit carried thereby topass between the. said plugs and flow into the interior of the hood 10.At the same time the water may flow through the by-path 23 into theinterior of the innerrtube 29. 'By reasonof the fact that the innerperiphery of the tube 22 comes in contact with the periphery of the corea which is being formed in the rock by the bit 2 sufiicient friction isafforded to hold the tube 22 stationary while the tube 1 rotates. At thesame time the column of water contained within the tube 22 above thecore also adds friction which tends to hold the said core 22'stationary. Inasmuch as streams of water are passing down along the sideof the ring 4 through the grooves '5 provided in the periphery thereof,said streams will have a tendency t6 hold the ring 4 in a. stationary.

position, and consequently thering will have no tendency to grind orwear the side of the core being formed in the rock. The ring 4 ismoreeffectually held in a stationary position by. reason of the factthat the recesses 5 areprovided with radially disposed walls 6 which areat those sides of the recesses 5 toward the direction from which theouter tube 1 is rotated. Therefore it will be seen that a simple andeifective means is provided for preventing the ingress of Water and gritto the cavity in the plug which houses the anti-friction devices betweenthe attached parts of the inner and outer tubes, and furthermoremeans-is provided for economically and effectually holding the innertube in stationary position, while the outer tube is rotated and alsofor holding the gripping or split ring in a stationary position whilethe adjacent outer tube and bit' are rotated.

Having thus described the invention what I claim as new and desire tosecure by Letend of the plug which closes the end of the 'stem'andfitting snugly against the lower tube, the inner-tube being connectedwith the last mentioned plug.

2. A double core barrel comprising spaced inner and outer tubes, ahollow plug located at the end of the outer tube and having a de-'pending hood which projects into the outer tube, sa-id hood having itsouter periphery spaced from the inner periphery of the outer tube, saidplug having a passage leading from its interior into the space betweenthe periphery of the hood and the outer tube, antifriction deviceslocated in the hood, a plug closing the end of the hood a stem journaledin said last mentioned plug andhaving bearings upon the anti-frictiondevices, a plug attached to the stem and closing theend of the innertube, the last mentioned plug having a by-pass leading from' itsexterlor into the interior of the inner tube, the adjacent faces of theplug which closes the end of the hood and the plug which is attached tothe stem fitting snugly against each other. I

3. A double core barrel comprising spaced inner and outer tubes, a bitattached to the outer tube below the lower end of the inner tube, saidbit having at its uppenend portion an internal bevel, a ring located inthe upper portion of the bit and adapted to bear against the bevelthereof, said ringhaving,

grooves provided upon its periphery and extending from one end of thering to the other end and forming unobstructed passageways.

4:. A double core barrel comprising inner and outer spaced tubes, a bitattached to the lower end of the outer tube and provided at its upperend with an internal bevel, a ring located in the upper end portion'ofthe bit and adapted-to bear against the bevel thereof, said ring havingupon its outer periphery grooves, which extend from one end-of the ringto the other and form unobstructed passage-ways, each groove having awall which is radially disposed and another wall which is tangentiallydisposed with relation:

to a circle struck from the centers of the tubes. t

In testimony that I claim theforegoingas my own, I have hereto aflixedmy signature in the presence of two witnesses.

I hIICI-IAEL AHEARNL I Witnesses I JAMES LAUGHLIN, BEN. BURDER.

